Distributed storage systems use hardware such as a central processing unit (CPU), one or more disc controllers, and a plurality of data storage devices logically grouped together as bulk storage. Computer program code operating on the CPU and/or disc controllers controls the manner in which user data is stored and accessed. User data can be stored in various fault tolerant schemes, such as in redundant array of independent drive (RAID) formats, for example. Multiple RAID formats can advantageously be employed concurrently within the storage system. The amount of available storage capacity, as well as the rate at which the storage capacity can be dynamically allocated, both significantly contribute to the storage system marketability.
The use of multiple disc arrays (MDAs) to mechanically define units of bulk storage results in a more reliable and a more readily scalable storage system. The multiple disc arrays are preferably a plurality of data storage devices that are both physically and logically grouped to function as a block of memory space to the storage system. Reliability is enhanced in that if a particular data storage device in the MDA is failing then it can be quickly and easily swapped out with a replacement data storage device. Scalability is enhanced by the ability to attach additional MDAs to the storage system and allocate them individually or collectively as logical devices as the need for storage capacity changes.
As these advantages spur the demand for more prevalent use of MDAs, attention will be directed toward effective and efficient carrier methodologies for them. Also, as storage density and processing time requirements continually result in ever-higher performance standards, vibration-related interferences that were once ignored as negligible come into play because they create data transfer errors. Individual data storage devices are designed to operate in a relatively high vibration environment, thereby decreasing the data storage capacity in terms of the number of tracks per inch (TPI) that the data storage device is capable of. If vibrations can be reduced, such as by reducing external excitations from other data storage devices in an MDA, then the TPI of a data storage device can be increased, thereby increasing its data storage capacity. What is needed is a solution offering both the flexibility of the MDA but within a mechanical structure that effectively eliminates rotational vibration interference (RVI). It is to these improvement features that the embodiments of the present invention are directed.